Tag: long distance transport of water

Questions Related to long distance transport of water

Which option is correct in relation to opening of Hydathodes.

  1. Opens during night hours.

  2. Opens during day hours.

  3. Opens during noon hours.

  4. Are always open


Correct Option: D
Explanation:

Guttation is the loss of water through water stomata (hydathodes) in solution form as a dilute solution of mineral salts. When the absorption of water exceeds transpiration i.e., when plants are absorbing actively, a positive root pressure is built up under the influence of which excess water simply oozes out through the dead ends of xylem tracheids and vessels. A loose collection of cells called as epithem, present at the dead ends of xylem tracheids and vessels. The epithem cells do not regulate opening and closing of hydathodes. Thus, hydathodes are unregulated openings and are always open. Thus, the correct answer is option D.

The word Guttation was given by

  1. Burgerstein

  2. Sayre

  3. Sacrth

  4. Stephen hales


Correct Option: A
Explanation:

Guttation is the loss of water through water stomata (hydathodes) in solution form as a dilute solution of mineral salts. The term was coined by Burgerstein in 1887. When the absorption of water exceeds transpiration i.e., when plants are absorbing actively, a positive root pressure is built up under the influence of which excess water simply oozes out through the dead ends of xylem tracheids and vessels. Thus, the correct answer is option A.

Water of guttation is

  1. Pure water

  2. Water with dissolved salts

  3. Solution of organic food

  4. Condensed water vapour


Correct Option: B
Explanation:

Guttation is the loss of water in solution form through hydathodes. The water lost in guttation is a dilute solution of mineral salts. The guttation occurs under the influence of positive root pressure and depends on environmental conditions. It is generally observed when atmospheric humidity is high so that rate of transpiration is low and soil is well watered. Thus, the correct answer is option B.

Guttation usually occur in a well watered herbaceous plant and well drained soil during

  1. Early morning hours

  2. Evening hours

  3. Noon hours

  4. Day hours


Correct Option: A
Explanation:

Guttation is the loss of water through water stomata (hydathodes) in the form of the dilute solution of mineral salts. When the absorption of water exceeds transpiration i.e., when plants are absorbing water actively, a positive root pressure is built up under the influence of which excess water simply oozes out through the dead ends of xylem tracheids and vessels. This usually happens during early morning hours when transpiration is low.

Guttation is common among the plants of $..........$ climate.

  1. Hot and wet

  2. Hot and windy

  3. Cold and humid

  4. Cold and windy


Correct Option: C
Explanation:

The exudation of xylem sap at the edges or tips of the leaves of some vascular plants, like grasses is called guttation. Unlike transpiration, it takes place only in certain conditions like cool and highly humid atmosphere. It is because plants can absorb up a limited amount of water. The excess water is secreted from the roots through the xylem and out through the hydathodes or water glands.

 






 

Guttation occurs when plants absorb water through

  1. Active absorption

  2. Passive absorption

  3. Root pressure

  4. Both A and C


Correct Option: D
Explanation:

When the plant absorbs water by their own, it is called active absorption. It takes place when transpiration is low and amount of water in the soil is high. In this case root hairs play the major role in the absorption of water. Root pressure is the positive pressure that develops in the roots of plants by the active absorption of nutrients from the soil. It causes sap to rise through a plant stem to the leaves. Guttation is the exudation of xylem sap on the tips or edges of leaves of some vascular plant. According to the passive absorption, root hairs do not play any role in absorption. It takes place only when transpiration rate is high. So, the correct option is D.

Guttation occurs through

  1. Hydathodes

  2. Lenticels

  3. Cuticle

  4. None of these


Correct Option: A
Explanation:

The process of exudation of sap on the tips or edges of leaves in plant is called guttation. It takes place only under certain conditions like cold and high relative humidity in the atmosphere. It occurs through the specialized structures called hydathodes. They are generally restricted to the apex or the edges of the margins of leaves. Structurally, hydathodes consist of a simple pore in the epidermal layer found at the tip.


The process of escape of the liquid from the tip of uninjured leaf or through hydathodes is called as

  1. Transpiration

  2. Guttation

  3. Evapo-transpiration

  4. Evaporation


Correct Option: B
Explanation:

Guttation is the excretion of drops of xylem sap on the tips or edges of leaves of some vascular plants, such as grasses. It is the loss of water in liquid form through hydathodes.

Therefore, the correct answer is option B.

Loss of water from the tip of the leaf pores in a plant is known as 

  1. Transpiration.

  2. Guttation.

  3. Evaporation.

  4. Respiration.


Correct Option: B
Explanation:

The soil rich in moisture content, water floods a plant root system. Leaves can retain only a finite amount of water. Excess water i.e xylem sap is given out from the roots through pores or edge of leaves and this process is called guttation. Thus the correct answer is option B.

Transpiration occurs through .......... and guttation occurs through .......... in the plants.

  1. Hydathodes, stomata

  2. Stomata, cuticle

  3. Stomata, hydathodes

  4. Hydathodes, lenticles


Correct Option: C
Explanation:

Transpiration is the process in which water vapors are released from the stomata. Guttation is the process of release of water droplets from the hydathodes.

So, the correct answer is 'Stomata, hydathodes'.